It is known to provide an arrangement to mount wheels, and particularly vehicular wheels, on a shaft, usually a vertical shaft, by engaging the wheel disk or the hub thereof with a frictional counter element on one side and to clamp the other side of the wheel against the counter element. To ensure tight seating, a conical arrangement or conical assembly may be interposed between the central or shaft or hub opening of the wheel and the balancing shaft. A spring may be provided to ensure that the conical arrangement seats tightly, and to bias the conical arrangement in a direction to provide for snug engagement of the conical assembly, typically including an expansible part with a cylindrical outer surface, with the centering hole of the wheel or the hub.
The referenced U.S. Pat. No. 4,918,986, Warkotsch, to which German Patent 38 08 755 corresponds, describes a quick clamping arrangement of this type in which the conical assembly is formed by two parts, one of which is freely axially shiftable on the shaft. The spring element is located either between the flange and the second part, or the second part is located against the flange and the spring is tightened or stressed against the first part of the conical assembly. Upon clamping the wheel, the hub is pressed against the flange and, further, the conical parts are relatively shifted axially such that the outer one thereof can radially expand by sliding against the inner one of the conical parts, thereby securely centering the hub opening in the wheel to be balanced on the balancing machine shaft.
It has been found in use that difficulties arise since the seating and clamping arrangements must be exchanged on the balancing machine shaft when different sizes of wheels are to be balanced. The conical assembly and the springs form loose parts of sets designed to accommodate differently sized wheels, with different hub openings on the balancing machine. In order to balance a specific wheel, the parts of the specific set must be assembled, fitted together, and only then can the wheel be balanced. This requires skill and a comparatively time-consuming assembly operation, all done by hand. The danger is ever present that parts from one set become intermingled with parts from another set and, before the respective sets can then be used, it is necessary to sort the individual parts which pertain to any specific set.
The arrangement is comparatively time-consuming in use since the spring, when being placed on the machine, is in unstressed position and a sufficiently long spring path must be overcome before the spring is sufficiently tight to provide effective spring biasing pressure. This requires overcoming a comparatively long spring travel path, usually by tightening a nut, or a screw, which further increases the time necessary to balance a specific wheel on the balancing machine.